I'm thinking about making some changes to my truck. I wanted to understand what I'm getting myself into before hand. I know little about turbo's and boose and how to modify boose and fuel etc. so I'm trying to learn before doing anything. Question that I have is how mods will effect fuel consumption. Guess I should ask what mods to make first.. I know I've read it on here before..
1.) Gauges
2.) 3.5 or 4" exhaust

Then what's next?

When does fuel economy start to suffer or is it all good?
Does the increase power reduce the life of the engine?

Thanks.

I'm thinking about making some changes to my truck. I wanted to understand what I'm getting myself into before hand. I know little about turbo's and boose and how to modify boose and fuel etc. so I'm trying to learn before doing anything. Question that I have is how mods will effect fuel consumption. Guess I should ask what mods to make first.. I know I've read it on here before..
1.) Gauges
2.) 3.5 or 4" exhaust

Then what's next?

When does fuel economy start to suffer or is it all good?
Does the increase power reduce the life of the engine?

Thanks.

Reflash

It's up to your right foot

Depends on how hard you treat it--if you tow heavy at WOT for example. EGT gauge will help you here.

Fuel milage can suffer when you're modified because you have the potential to burn a greater quantity of fuel at any given acceleration. That said I'm waiting to deplete my first full tank of #2 on the '96 to see what milage I'm getting with the changes I've made in the block/heads.

Work on getting more cooler air to the engine for good economy.
The KAT would be the first to go in fuel robber.

Yeah - the more booze you have, the more trouble you can get into with the turbo.................):h

Drive like you have an egg between your foot and the accel pedal & keep the engine RPM as low as possible for fuel economy & componets long life. If you don't tow heavy change the rear axle to a 3.08 & don't drive at more than 1600 RPM on the road. These conditions would keep the engine operating for at least 500.000 mi. Not that your going do them all, but keep the statements in the back of you mind. Kind of like a "brain reflash".

Back to one of your questions...yes, fuel economy has potential to improve if driving habits don't change (mine did). Engine doesn't have to work as hard cuz it's more powerful...to a point :D .

take the "mine did" as you will :ro) .

and yes, I have a different engine, but the principle is the same...enjoy! :)

I usually baby my truck. Slow easy starts and all. Then I was thinking that since max torque is around 2000rpms that stepping on the pedal to get her to 2K sooner would be better all around. Still on the first tank of gas but looks like I'm burning more fuel.
My truck runs great and gets avg 16mpg. Getting a bigger boat so I'd like more towing power. Just don't want to screw up what I got.. If mod will get better then 16mgs when not towing and loose a little when towing because she's pulling more I'm good.. Just don't want to drop to something like 13mpg avg without towing because of the mods.

If you're towing heavy... even STOCK, get a pyro and keep the EGT's below 1400, and don't run extended distances at 1300... downshift, and slow down to let it cool down.


Bigger tunes make it much easier to overheat the exhaust when towing, which is why Diablosport says something like "Okay to tow on 40hp, tow no more than 7k on 60hp, don't tow on 90hp"

Rich: What or who is Diablosport? Can you explain what ok to tow on 40hp and don't tow on 90hp means?

Thanks.

Diablosport makes the Predator tuner. It's a box like the BullyDog Power Pup that does not remain in the truck, it merely downloads it's tune into your PCM.

Standard recommendation is that you can drive/tow as normal on the low HP tunes. Above the "first level", most tuners recommend that you have boost and pyro gauges to monitor the engine parameters, and also suggest that you scale back the amount of "work" that the truck does, to the point that towing is not recommended on the tunes that add 90hp or more to the base engine parameters.

Exhaust temperature is a killer... it can damage the turbo, as well as potentially burn valves (but the turbo is most likely to be damaged).
Cruising down the freeway building 5-10psi of boost, you're probably going to be looking at exhaust temps of 600-900 degrees.
Climbing a hill, it can get up to 1200 or so. Trying to pass someone going up a hill and building 20-25psi, you can see 1300+.

You want to minimize the time spent above 1100-1200.

High-performance tuners add more fuel and tweak the timing to produce more power. It's pretty simple, and relatively safe, since a "lean" Diesel isn't going to burn a hole in the piston, but unless airflow (turbo boost/volume) is increased commeasurate with the fuel, exhaust temperatures will rise.
Throw on a trailer and they rise more.

Running 90hp over stock, you can get into risky territory climbing a grade without towing.

I resently upgraded my 99' Sub, like yours (see sig). If you have a "F" as the 8th digit in your VIN you have the "heavy duty" motor, which is a good thing. Your motor isn't restricted with smog stuff. A larger exhaust system and gauges is a good place to start with. ( A remote PMD would be advisible too, for reliability. Sure would suck to be broken down somewhere with a boat on your bumper. ) I have read that the factory downpipe looks like it was driven over with a big rig.. When I replaced my exhaust that statement seemed to be accurate. The big deal is to get the hot exhaust gas out fast as possible to keep EGT down. You aren't going to feel big power gains but the sound will make you smile. A PCM reflash and boost controller will give you the power gains. I talked with a couple of people that sell "performance packages" for 6.5TD's and Bill Heath from Heath Diesel was the most sincere in my many conversations with him. I would give him a call and ask questions. Bill will probably answer the phone and if not ask for him.

The guy I bought my Suburban from towed a travel trailer which weighed about 6500#'s and the truck was all stock. He said "I wouldn't tow much more than that though". With my upgrades I should have no problems towing my travel trailer at 8500# now. I have a nice and noticable difference gain in power. As for mileage I am not getting as many MPG's now since my right foot has gotten a little heavyier. I am starting to drive like I used to. Soon I will check my mileage again to see if there is any difference..

When I got my Stinger Kit from banks it stated 10psi boost as max safe and 1050 exhaust temp max safe post turbo . Ive run her higher on grade but not for any length of time . I did not see any noticeable difference in mileage from it . I wish I would have pulled the cat off during the install but plan too soon . I have since then pulled the stock air box , cut open the air inlet hole from the fender to more than twice the stock size . Also made an alum air box and added a 9" cone filter . Dunno if it helped with mileage yet butyou can sure hear the tubo spool now .

Most guys are measuring pre-turbo.... it's a couple hundred higher.